A mother who lost her daughter in the Lockerbie attack has condemned the “cold, callous and brutal” behaviour of British ministers after WikiLeaks documents revealed how they secretly advised Libya on securing the successful early release of the bomber.

Documents obtained by the Daily Telegraph show that a Foreign Office minister sent Libyan officials detailed legal advice on how to use Abdelbaset al-Megrahi’s cancer diagnosis to ensure he was released from a Scottish prison on compassionate grounds.

The Duke of York is also said to have played a behind-the-scenes role in encouraging the terrorist’s release.

The Libyans closely followed the advice which led to the controversial release of Megrahi – who was convicted of the murder of 270 passengers on Pan Am Flight 103 – within months of the Foreign Office’s secret intervention.

The Daily Telegraph today publishes more than 480 American documents detailing international relations with the Libyan regime over the past three years....